If you have kids, the conversations sometime wander into strange areas. I was told yesterday that the U.S. Defense budget was 54% of the U.S. budget. I said that not right, even though Siri was telling him otherwise.
It turns out that in 2015 that the U.S. Defense budget was 54% of U.S. discretionary spending, according to Wikipedia. This is a significant distinction. In 2015 the U.S. defense budget was $598 billion. In 2015 the U.S. Federal budget was $3.688 trillion actual (compared to 3.9 Trillion requested). This is 16% of the U.S. budget. As always, have to read carefully.
Just to complete the math, the U.S. GDP in 2015 was 18.037 Trillion (United Nations figures). So, federal budget is 20% of GDP (or 22% is the requested budget figure is used) and defense budget is 3.3% of GDP.
Latest figures are 583 billion for U.S. Defense budget (requested for 2017), 3.854 estimated expenditures for the U.S. Federal Budget for 2016 and 4.2 trillion requested for 2017, and 18.56 trillion for U.S. GDP (2016) and 19.3 trillion (preliminary for 2017).
Sources:
https://en.wikipedia.org/wiki/Military_budget_of_the_United_States
https://en.wikipedia.org/wiki/United_States_federal_budget
https://en.wikipedia.org/wiki/Economy_of_the_United_States#21st_century
And other wikipedia links.